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  <script>
    var sortArrayByParity = function (A) {
      let num = A;
      let res = [];
      for (let i = 0; i < num.length; i++) {
        if (num[i] % 2 == 0) {
          res.push(num[i])
        }
      }
      for (let j = 0; j < num.length; j++) {
        if (num[j] % 2 != 0) {
          res.push(num[j])
        }
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      return res
    };
    console.log(sortArrayByParity([3, 1, 2, 4]))
  </script>
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